Tusa X-Pert Z-3 Zoom FinsX Pert Z 3 Zoom Fins Over 5 years of research and development brought the highly regarded and best selling SF 8 X Pert Zoom split fin to market in 2003. TUSA redefines the fin market again with the introduction of the SF 15 X Pert Zoom Z3. The SF 15 further improves upon the performance, features and design of the SF 8 with the incorporation of 3 materials, 10% longer blade length, enhanced propeller fin technology, reinforced blade rails and